Observers tracking EPA's implementation of the new TSCA law said last spring shortly before the suit was filed that it would provide a test case for the agency's interpretation that petitioners must provide a comprehensive analysis of all uses of a chemical in order to seek a restriction on a particular use.

“This asserted view, that only a comprehensive risk evaluation considering all conditions of use will suffice, presents a very high threshold for action -- and seemingly an impossibly high threshold to move EPA to act," stated a blog post from the law firm Bergeson & Campbell March 7.

The novel rationale for rejecting the request drew the attention of the firm, which suggested in the blog that the interpretation essentially obviates the purpose of section 21 petitions for agency action under section 6, which has traditionally been to draw the agency's attention to a chemical hazard that had not previously been a focus.

EPA's denial outlined general obligations petitioners should meet in seeking chemical restrictions under the updated version of the toxics law. “This requirement includes addressing the full set of conditions of use for a chemical substance and thereby describing an adequate rule under TSCA section 6(a) -- one that would reduce the risks of the chemical substance 'so that the chemical substance or mixture no longer presents' unreasonable risks under all conditions of use,” the agency said.

“Rather than comprehensively addressing the conditions of use that apply to a particular chemical substance, the petition requests EPA to take action on a single condition of use (water fluoridation) that cuts across a category of chemical substances (fluoridation chemicals),” the agency added.

Bergeson and Campbell attorneys said that EPA's denial is "essentially arguing that since EPA must assess 'all conditions of use' in any control rule they might promulgate, then any outside petition must include all of the same homework before it can be granted.”